At user administration interface, writing a “login” triggers the visualization of a live list with possible matches – somewhat similar to the “instant search” results.

In our opinion, it would be useful to include that feature on record edition mode - when selecting the record's (sub)category.

It could (should?) be implemented in parallel with the current one.

This is specially important if there is a large number of categories/subcategories, and/or there is a deep subcategory nesting – not a good practice, but (unfortunately) quite common.

A side note:
the trash icon colors may lead to some degree of confusion (specially on the category administration page) and/or access difficulties to persons with color vision deficiency.

A fast (and “raw”) suggestion: using

a “white” icon for available delete operation,

a cross or a diagonal line over the icon related to “non deletable” (restricted) item,

a dark icon if the delete operation is not allowed (but the item is not restricted).

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We'll try to post another article about the difficulties / different interpretations that many of our users (with different backgrounds) present to us about categories management, their visualisation and access restriction (in edit mode and in standard web's access).
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Kind regards
2014-06-17
pt20100201
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